Hydration and primary headaches in children and adolescents: a prospective interventional study

Objective Primary headaches are a prevalent health concern among children and adolescents, often affecting their quality of life. Emerging evidence suggests that hydration status may play a role in primary headache occurrence and severity. This study aimed to evaluate the impact of hydration on headache characteristics in children and adolescents with primary headaches. Methods A total of 60 children and adolescents diagnosed with primary headaches were enrolled from the outpatient Headache Clinic of the Department of Paediatric Neurology at the University Children’s Hospital, University Medical Centre Ljubljana, Slovenia, between May and September 2023. Participants received personalised hydration recommendations based on established Slovenian dietary guidelines and guidance on appropriate fluid choices. The primary outcome was headache frequency, intensity, and duration, measured at baseline and after the four-month intervention using a headache questionnaire. Fluid intake was assessed using a Food Frequency Questionnaire, while hydration status was evaluated in a sub-group (n=28) using bioelectrical impedance analysis. Results Following the four-month intervention, participants demonstrated a significant increase in daily fluid intake from 5–8 glasses/day (one glass=200 mL) to 8–10 glasses/day (p<0.001), which was associated with a reduction in primary headache frequency (1–2 times/week to 3 times/month; p<0.001) and headache intensity (7/10–5/10; p<0.001). However, no significant effect was observed on headache duration (3 hours/headache to 2 hours/headache; p=0.19). Following the intervention, hydration status improved, as evidenced by significant increases in median total body water and extracellular water (p<0.001 and p=0.007, respectively), while the total body water to extracellular water ratio remained unchanged. Conclusions This study provides novel evidence supporting adequate fluid intake and hydration as a non-pharmacological intervention for reducing primary headache frequency and intensity in paediatric populations.